Meaningful Ethics Reforms for the New Albany

The corruption scandals of the last few years have profoundly shaken the faith of New Yorkers in their state government. This report examines the system erected by New York's current ethics laws and makes clear recommendations for a way forward

Synthesis and Characterization of Model Acrylic-Based Polymer Gels

Materials made from polymer gel networks are important to many everyday applications in health care to building materials. These gel materials can be easily synthesized in various ways, but characterizing the overall material mechanics and properties are challenging due to the soft nature of their respective bulk structures. Model acrylic-based copolymer gels were investigated to understand the fundamental characteristics and mechanical properties from different crosslinking and gelation processes. First, model hydrogels with fracture-healing characteristics similar to materials needed for injectable drug delivery systems were studied using shear rheology to determine timescales of fully healed networks. The industrially available gel was a thermoreversible triblock copolymer composed of poly(methyl methacrylate)-poly(n-butyl acrylate)-poly(methyl methacrylate) in 2-ethyl hexanol to form a physical gel from polymer-solvent interactions. A methodology of quantifying healing was developed from an applied constant shear rate and monitoring the shear stress response of the samples. The maximum shear stress responses observed during fracture and re-fracture after allowing the sample to rest indicated gel healing. Given sufficient time, gel healing was determined to be dependent on testing temperature and polymer volume fraction. The time for fully healed networks was achieved on the order of minutes for the lowest volume fraction of 5 vol. % at temperatures of 28 and 25°C to several hours for the highest volume fraction of 6 vol. % at lower temperatures of 23 and 20°C. Lastly, spherical superabsorbent polymer (SAP) gels with silica nanoparticles (SiO2) were synthesized from inverse suspension polymerization to form chemically crosslinked composite hydrogels of polyacrylamide and poly(acrylic acid). The hydrogels were studied for understanding the interaction of SiO2 nanoparticles within polyelectrolyte networks for use as a chemical admixture for internal curing of high performance concrete. The composite SAP hydrogels were produced with bare or silane-functionalized SiO2 particles to investigate the effects on swelling performance, shape, and cement paste microstructure

tRNA functional signatures classify plastids as late-branching cyanobacteria.

BackgroundEukaryotes acquired the trait of oxygenic photosynthesis through endosymbiosis of the cyanobacterial progenitor of plastid organelles. Despite recent advances in the phylogenomics of Cyanobacteria, the phylogenetic root of plastids remains controversial. Although a single origin of plastids by endosymbiosis is broadly supported, recent phylogenomic studies are contradictory on whether plastids branch early or late within Cyanobacteria. One underlying cause may be poor fit of evolutionary models to complex phylogenomic data.ResultsUsing Posterior Predictive Analysis, we show that recently applied evolutionary models poorly fit three phylogenomic datasets curated from cyanobacteria and plastid genomes because of heterogeneities in both substitution processes across sites and of compositions across lineages. To circumvent these sources of bias, we developed CYANO-MLP, a machine learning algorithm that consistently and accurately phylogenetically classifies ("phyloclassifies") cyanobacterial genomes to their clade of origin based on bioinformatically predicted function-informative features in tRNA gene complements. Classification of cyanobacterial genomes with CYANO-MLP is accurate and robust to deletion of clades, unbalanced sampling, and compositional heterogeneity in input tRNA data. CYANO-MLP consistently classifies plastid genomes into a late-branching cyanobacterial sub-clade containing single-cell, starch-producing, nitrogen-fixing ecotypes, consistent with metabolic and gene transfer data.ConclusionsPhylogenomic data of cyanobacteria and plastids exhibit both site-process heterogeneities and compositional heterogeneities across lineages. These aspects of the data require careful modeling to avoid bias in phylogenomic estimation. Furthermore, we show that amino acid recoding strategies may be insufficient to mitigate bias from compositional heterogeneities. However, the combination of our novel tRNA-specific strategy with machine learning in CYANO-MLP appears robust to these sources of bias with high accuracy in phyloclassification of cyanobacterial genomes. CYANO-MLP consistently classifies plastids as late-branching Cyanobacteria, consistent with independent evidence from signature-based approaches and some previous phylogenetic studies

Sodium-activated potassium channels are functionally coupled to persistent sodium currents

We report a novel coupled system of sodium-activated potassium currents (I(KNa)) and persistent sodium currents (I(NaP)), the components of which are widely distributed throughout the brain. Its existence and importance has not been previously recognized. Although I(KNa) was known to exist in many cell types, the source of Na(+) which activates I(KNa) remained a mystery. We now show in single membrane patches generated from the somas of rat neurons that sodium influx through I(NaP) is sufficient for activation of K(Na) channels, without substantial contribution from the transient sodium current or bulk [Na(+)](i). I(NaP) was found to be active at cell membrane resting potentials, a finding that may explain why I(KNa) can be evoked from negative holding potentials. These results show an unanticipated role for I(NaP) in activating a negative feedback system countering the excitable effects I(NaP); the interrelatedness of I(NaP) and I(KNa) suggests new ways neurons can tune their excitability

The evolution of 10-K textual disclosure: Evidence from Latent Dirichlet Allocation

Abstract We document marked trends in 10-K disclosure over the period 1996–2013, with increases in length, boilerplate, stickiness, and redundancy and decreases in specificity, readability, and the relative amount of hard information. We use Latent Dirichlet Allocation (LDA) to examine specific topics and find that new FASB and SEC requirements explain most of the increase in length and that 3 of the 150 topics—fair value, internal controls, and risk factor disclosures—account for virtually all of the increase. These three disclosures also play a major role in explaining the trends in the remaining textual characteristics

Use of antisense oligonucleotides to enhance exon 7 incorporation in the pre-mRNA splicing of SMN2

Abstract only availableSpinal muscular atrophy (SMA) is a neurodegenerative disorder that is relatively common in humans and is caused by loss of the survival motor neuron 1 (SMN1) gene. SMA is the leading cause of hereditary infant mortality by causing anterior horn cell degeneration in the spinal cord resulting in trunk and limb paralysis. The survival motor neuron 2 (SMN2) gene is located proximally to the SMN1 gene on chromosome 5q and the two genes are almost identical. Interestingly, only mutations in SMN1 cause SMA, whereas mutations in SMN2 have no clinical consequence. A differential pre-mRNA splicing event results in SMN2s failure to compensate fully for SMN1 mutations. Exon 7 is excised during SMN2 RNA splicing and this causes expression of a non-functional gene product. SMN2 produces the SMN protein at low levels (~10% compared to SMN1) but not enough to compensate for the loss of SMN1. Previous studies have shown that the use of antisense oligonucleotides can significantly decrease recognition of the 3' splice site of exon 8, resulting in an increase in increased levels exon 7 inclusion in SMN2-derived transcripts. Here, we have developed in vivo expression vectors that generate antisense oligonucleotides spanning two regions of the SMN2 transcript: a repressor exon 7 splicing “repressor” region and the exon 8 splice acceptor site. We are adding a pol III terminating sequence downstream of the antisense sequences to ensure that the clones are only making short oligos. If successful, these vectors could be used to increase SMN protein expression in an SMA context and may open a new area of SMA therapeutics, as well as providing a fundamental basis for treating other genetic disorders where splicing events are the main cause of disease.Molecular Biology Progra

In-Situ measurement of hydride corrosion of uranium using X-ray and neutron scattering techniques

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A combined "electrochemical-frustrated Lewis pair" approach to hydrogen activation: surface catalytic effects at platinum electrodes

Herein, we extend our “combined electrochemical–frustrated Lewis pair” approach to include Pt electrode surfaces for the first time. We found that the voltammetric response of an electrochemical–frustrated Lewis pair (FLP) system involving the B(C6F5)3/[HB(C6F5)3]− redox couple exhibits a strong surface electrocatalytic effect at Pt electrodes. Using a combination of kinetic competition studies in the presence of a H atom scavenger, 6-bromohexene, and by changing the steric bulk of the Lewis acid borane catalyst from B(C6F5)3 to B(C6Cl5)3, the mechanism of electrochemical–FLP reactions on Pt surfaces was shown to be dominated by hydrogen-atom transfer (HAT) between Pt, [Pt[BOND]H] adatoms and transient [HB(C6F5)3]⋅ electrooxidation intermediates. These findings provide further insight into this new area of combining electrochemical and FLP reactions, and proffers additional avenues for exploration beyond energy generation, such as in electrosynthesis

Novel B(Ar')2(Ar'') hetero-tri(aryl)boranes: a systematic study of Lewis acidity

A series of homo- and hetero-tri(aryl)boranes incorporating pentafluorophenyl, 3,5-bis(trifluoromethyl)phenyl, and pentachlorophenyl groups, four of which are novel species, have been studied as the acidic component of frustrated Lewis pairs for the heterolytic cleavage of H2. Under mild conditions eight of these will cleave H2; the rate of cleavage depending on both the electrophilicity of the borane and the steric bulk around the boron atom. Electrochemical studies allow comparisons of the electrophilicity with spectroscopic measurements of Lewis acidity for different series of boranes. Discrepancies in the correlation between these two types of measurements, combined with structural characterisation of each borane, reveal that the twist of the aryl rings with respect to the boron-centred trigonal plane is significant from both a steric and electronic perspective, and is an important consideration in the design of tri(aryl)boranes as Lewis acids